Question 503674
Let {{{a}}} = liters of oil
{{{ (8/(3 + 8))*a }}} = liters of gas
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{{{ 73a + 35*(8/11)*a = 2000 }}} (in cents)
Multiply both sides by {{{11}}}
{{{ 803a + 280a = 22000 }}}
{{{ 1083a = 22000 }}}
{{{ a = 20.314 }}}
{{{ (8/11)*a = 14.774 }}}
{{{ 20.314 + 14.774 = 35.088 }}}
35.088 liters of the mixture can be made 
for $20